Dendrochronology

Abstract

Dendrochronology also known as tree ring dating is the science of studying climatic change in a region by use of tree rings. It is efficient because tree rings are formed yearly caused by seasonal changes like moisture or temperature availability. Environmental contribution like regional climatic changes bring about distinguishable ring patterns depicted as varying width of a ring or chemical composition of cell walls. Generally good conditions make a tree grow well and vice versa thus making them a good climate indicator.

It unclear of the aftermath expected as a resultant of increased carbon dioxide emission, to the misuse water consumption and the forest cover. However it is evident of what will be the effects of this gas and forest future distribution. Some research has been conducted on some sites and studies of seedlings, the results are not reliable because of some factors like short durations or artificial increases in carbon dioxide concentration. It is important to note that the International Tree ring Data Banks' records indicate that increasing growth rates and drought sensitivity decrement can't be solely clarified by climatic change alone. In the final analysis of these findings it is true that future forest dynamics could possibly differ on the current ones on condition that, the response to increase carbon dioxide by individual and site conditions. IN addition it seems that forest fertilization by carbon dioxide won't slow down warming in any way or counteract emissions

INTRODUCTION

It is evident that in the future forest cover distribution will depend on the response given by the trees because of increased carbon dioxide transmission, (Tree Ring Society, 1975).  It is worth to note that though trees can reverse increased manmade greenhouse emissions it is difficult to quantify their effects.

Increased growth of trees can be simulated through elevated carbon dioxide levels; The first option being as an occurrence Increased water use efficacy may happen due to reduced stomatal conductance resulting to drought sensitivity and thus accommodation of  species distribution in xeric surroundings, (Tree Ring Society, 1975). Secondly it is through direct carbon dioxide fertilization may occur because higher partial pressure of carbon dioxide increases its rates of reactions with rubisco during photosynthesis. It has been quantified through long term research on mature trees brought about growth rates based on dendrological evidence that radial growth a relatively low priority for allocation of carbon in trees, translating to  during only years of unusually high photosynthate production wide rings are typical. (CCS Blog, 2010). I believe that any increase in productivity as a result of carbon dioxide inducing should be witnessed as a increase in growth rates.

From the Dendrological perspective the issue of carbon dioxide fertilization has been restricted to the analysis of a few locations thus inefficient and conflicting results, (American Geophysical Union, 2010). Though at global ring  records it is realized that  increased  growth can't be as a result of climatic trends Growth sensitivity to drought. Notably tree rings are indicators of carbon dioxide fertilization due to tree bores which are lands most recurrent pool of biomass carbon. A noticeable sign denotes a detectable change in storage (CCS Blog, 2010). It is inevitable to address the issue of individual species adaptability to counter the changing climate.

For instance in my case study  I choose tree samples from a parking lot where a tree is more prone to emissions and the other samples from a park. The trees from the park as per the results, the ring width showed that there was much growth. Much has been invested in research  tree rings  have all along been used by scientists to develop techniques needed to develop  and reconstruct the climate. During the recent the climate and tree ring association has declined with no concern addressed to it at all. It is true that the greenhouse effect is real and uncontroversial. Increased carbon dioxide has a impact on plants, in photosynthesis  for example, increased carbon dioxide in the air can increase plant growth and leading to drought insensitivity an expected response by plants to high carbon dioxide exposure.

Decreased drought sensitivity is an expected response for plants exposed to high levels of carbon dioxide. All along the underside of a plant's leaves are little holes called "stomata." These holes can open and close. A tree must open its stomata to take in carbon dioxide for photosynthesis. Unfortunately, plants lose water out of their open stomata. Plants growing in air that has lots of carbon dioxide can reduce the amount of time their stomata are open, thus making them lose less water and become less susceptible to drought.

"Water-use efficiency," as referred to by biologists is of crucial interest to farmers and to everyone is explained. To begin with there are little holes under a leaf, the stomata. The stomata must open to take in carbon dioxide for photosynthesis and through the same holes they lose water. It is possible that plants growing in air with high carbon dioxide concentrations can reduce the time they open their stomata thus losing less water and less danger to drought. 

METHODS

In this case samples are taken and measurements of the width of annual rings. This is done by taking samples from different sites and different types of trees. In my case study I sampled trees from the parking lot and from the park. The cores I had extracted were from five trees. Particularly the standard measurements I used t measure annual rings were in millimeters. In possession I had a tree corer or an increment borer, for drilling through a tree and getting tree cores. This tool is T shaped; point the borer directly to the tree, holding safely to the tree. Hold the equipment, point the tip of the borer, push and rotate it. Drill till the borer is approximately near the center of the tree and be careful not to wiggle the machine because if wiggled the core is damaged and the tree rings unfit to read.

At this point an extraction rod is put through the hole which is in the middle of the handles and to release the tree core rotate the borer anticlockwise. Caution and care must be observed when pulling out the extraction rod so as to get a quality tree core sample. Store the core in a drinking straw. Continue with the turning of the borer so as to withdraw the borer. The sample is then taken to the lab for analysis where it is air dried and mounted. The next step is where it is sanded a step necessary to making the tree rings visible. An ocular is used to measure the width of each growth year as depicted by the tree rings under a magnification by the microscope. The measurements are taken under an eyepiece after it has been turned and a ruler lined up for measurements.

RESULTS

The first sample throughout the study has had a high annual growth rate.  Between two to three years there was a significant decline in annual radial growth. I collected five rings and the ring width was declining. The second species had the lowest annual growth, yet the most steady growth rate only fluctuating between 0.5mm to 1mm throughout the period of study. Large fluctuations in annual radial growth indicate that sample three was highly sensitive to the environment. The other sample had a steady decline in annual radial growth which possibly I think is as a result of the large standard error I have seen in my of the rings due to the use of only three core. Additionally each core was of a different species five in number, I only studied a species which was hard to read due to many false rings and as observed the growth seemed to be erratic. Mostly probably this is a representation of measurement errors and not the true growth pattern which seems to contradict the notion that annual radial growth decreases with time

DISCUSSION/CONCLUSION     

To be precise the second sample was from a parking park where the tree had been exposed to carbon dioxide emissions and making an inference to the effect of carbon dioxide on plants Increased carbon dioxide has a impact on plants, in photosynthesis for example, increased carbon dioxide in the air can increase plant growth and leading to drought insensitivity an expected response by plants to high carbon dioxide exposure. It is inevitable to address the issue of individual species adaptability to counter the changing climate. For instance in my case study  I choose tree samples from a parking lot where a tree is more prone to emissions and the other samples from a park. The trees from the park as per the results, the ring width showed that there was much growth. An error was made in the measurements it can be corrected through a more cautions and careful approach to the study. A study on much older trees would of great concern to me because of more research on mature trees from a dendrological view concerning carbon dioxide allocation and radial width.

In fact with reference to other scholars, from the Dendrological perspective the issue of carbon dioxide fertilization has been restricted to the analysis of a few locations thus inefficient and with conflicting results,(American Geophysical Union, 2010). believe I am justified to attest if more is invested in terms of research to the tree ring and climate relationship a groundbreaking solution might be the fruits.